A common source of these 
A common source of these particles is a device named for Farnsworth and Hirsch. Direct observation of magnons and phonons is possible via Brockhouse's triple-axis spectroscopy, which employs inelastic scattering events of these particles. Due to these particles, metastable structures called intimate Frenkel pairs can develop in materials like graphite; those materials must be heated in a process called annealing to relieve the Wigner energy that builds up when bombarded by these particles. Violation of CP symmetry by the strong force would require an electric dipole moment for this particle a trillion times greater than the maximum current prediction. The emission of energetic examples of these particles sustain fission reactions, and their number is different for an element's isotopes. For 10 points, name these particles composed of one up and two down quarks, the chargeless component of the nucleus.
A common source of these particles is a device named for Farnsworth and Hirsch.
{neutrons}